KR20050087731A - High pressure discharge lamp - Google Patents

Abstract

The present invention provides a short shot arc discharge lamp in which a stress generated in the seal portion is suppressed during the lighting of the lamp, and the seal portion is not broken, and the short such that the branch pipe portion is not broken does not occur. An arc discharge lamp is provided. The short arc type discharge lamp of the present invention is a short arc type discharge lamp in which a mount portion consisting of an internal lead rod, a tubular body, a metal body, a metal foil part, a blockage body, a second metal body, and an external lead rod is formed. The sealing body which sealed the said metal foil part with the sealing glass body which has an inner diameter larger than the outer diameter of a mount part is arrange | positioned in the said branch pipe part, The said branch pipe part and the said seal body are welded.

Description

High Pressure Discharge Lamps {HIGH PRESSURE DISCHARGE LAMP}

The present invention relates to a short arc type discharge lamp. In particular, it is a large high-input lamp which emits ultraviolet rays used for exposure of semiconductors or liquid crystal substrates, etc., and relates to a short arc type discharge lamp which is characterized by the structure of a sealing portion which intercepts a discharge space and the outside.

Conventionally, metal foils such as molybdenum and the like are used for the purpose of securing airtightness in the discharge space and the outside of the lamp while maintaining a high lighting pressure when the short arc type discharge lamp used for exposure of a semiconductor or a liquid crystal substrate is turned on. The method of sealing and sealing is used. Fig. 5 shows a short arc type discharge lamp of a so-called foil seal type that is sealed using a metal foil. The short arc discharge lamp 51 includes a bulb portion 52 and branch pipe portions 53 protruding from both ends of the bulb portion 52. In addition, an anode 54 and a cathode 55 are disposed in the bulb 52. In addition, the bulb portion 52 forms a discharge space so that, for example, about 1 atm of xenon gas is sealed as a rare gas inside the bulb portion 52, and mercury is, for example, 1 mg / dl as a light emitting material. To about 10 mg / dl. The positive electrode 54 and the negative electrode 55 are connected to one end of the internal lead rod 56a or 56b. The other end of the inner lead rod 56a on the side of the anode 54 is inserted into a tubular body 57 made of quartz glass and electrically connected to a washer-shaped metal body 58 to form a part of the mount 64. Consists of.

The mount portion 64 includes the inner lead rod 56a, a tubular body 57 supporting the inner lead rod 56a, a metal body 58 electrically connected to the inner lead rod 56a, The metal foil portion 59 in contact with the metal body 58, the metal foil portion 59 are disposed on an outer circumferential surface, and disposed at an end portion of the half discharge space side of the obstruction body 60. A second metal body 61 electrically connected to the metal foil portion 59, an external lead rod 63 connected to the second metal body 61, and capable of being fed from the outside, and the external lead rod 63; It consists of a 2nd tubular body 62 which supports. The mount portion 64 is inserted into the branch pipe portion 53 and is sealed to the branch pipe portion 53 through the metal foil portion 59 disposed in the mount portion 64. In addition, in the gap portion 60a between the metal foil portions 59 in the circumferential direction of the mount portion 64, the obturator 60 and the branch pipe portion 53 are sealed by melting at respective interfaces. . Thus, the technique of sealing using metal foil is described, for example in Japanese Patent No. 3379438. On the other hand, since the branch pipe part 53 on the positive electrode 54 side and the branch pipe part 53 on the negative electrode 55 side shown in FIG. 5 have the same configuration, the description of the negative electrode 55 side will be described here. Omit.

By the way, with respect to the short arc type discharge lamp 51 shown in FIG. 5, in the market, the throughput at the time of semiconductor processing is improved, and the processing ability at the time of large area irradiation to a liquid crystal substrate or a color filter is improved. Is required. It is the present situation that responds to these requests by making the input electric power to the said short arc type discharge lamp 51 higher than ever before.

However, as the input power is further increased, not only the bulb portion 52 and the branch pipe portion 53 are enlarged, but also the weight of the electrode portion is greatly increased by the enlargement of the anode 54 and the cathode 55 itself. It became heavy and the problem that handling at the time of manufacture became difficult has arisen. As a specific example, the input power is 12 KW, and the size of the bulb portion 52 is about 120 mm in outer diameter and about 160 mm in length, and the anode 54 is required to have an outer diameter of 30 mm, a length of 60 mm and a weight of about 1 Kg. . In addition, the lamp current at the time of lighting becomes high by high input, and it is necessary to increase the number of metal foils arrange | positioned in the outer peripheral direction of the obstruction body 60 of the said mount part 64, and respond to high current. In the case of sealing such a mount portion 64, a problem arises in that wrinkles are formed in the metal foil portion 59 after sealing or the foil itself is broken due to the above-mentioned heavy electrode or the like. In addition, while the lamp is turned on, the pressure in the bulb portion 52 becomes very high. As the electrode is enlarged, stress is concentrated between the bulb portion 52 and the branch pipe portion 53. In this case, the metal foil portion 59 also overlaps with the wrinkles, resulting in a problem in which the branch pipe portion 53 is broken. In addition, when the number of metal foils is increased in order to cope with a high current, the gap between the metal foils arranged in the outer circumferential direction of the occluded body 60 becomes very small, which makes the handling at the time of manufacture more difficult.

The problem to be solved by the present invention is a large short arc discharge lamp, in particular, a short arc discharge lamp having an input power of 10KW or more, the foil seal portion is not broken, and the airtightness between the discharge space and the outside (외부 To provide a seal structure that sufficiently secures vi). The present invention also provides a short arc type discharge lamp which suppresses stress generated between the bulb portion and the branch pipe portion when the lamp is turned on, and does not cause a defect such as bending of the branch pipe portion. Moreover, it is providing the short arc type discharge lamp which is easy to handle at the time of manufacture even in the case of a large short arc type discharge lamp whose input electric power is 10KW or more.

The short arc type discharge lamp of this invention has a bulb part which forms a discharge space, and the branch pipe part which protrudes in the both ends of the said bulb part, A pair of electrodes are opposingly arranged in the said bulb part, In the said branch pipe part, An inner lead rod in contact with the electrode, a tubular body supporting the inner lead rod, a metal body electrically connected to the inner lead rod, a metal foil portion in contact with the metal body, and a closed body in which the metal foil portion is disposed on an outer circumferential surface thereof And a second arc body disposed at an end side of the occluder and electrically connected to the metal foil, and a mount portion having an external lead rod connected to the second metal body to enable power supply from the outside. In the type discharge lamp, a seal body sealing the metal foil portion with a sealing glass body having an inner diameter larger than the outer diameter of the mount portion is disposed in the branch pipe portion, The branch pipe part and the seal body are welded.

The distance from the end of the tubular body supporting the inner lead bar disposed on the inner lead bar side of the seal body to the end of the discharge space side of the sealing glass body provided on the outer surface of the seal body is a, the When the glass thickness in the radial direction of the sealing glass body is b and the glass thickness in the radial direction of the glass tube constituting the branch pipe part is d, the relationship of a / b> 2 and b / d <1 is satisfied. Characterized in that.

Best Mode for Carrying Out the Invention

The short arc type discharge lamp of this invention welds the seal body which covered the outer periphery of a mount part with quartz glass in the branch pipe part which protrudes to both ends of a bulb part. In addition, an electrode or the like is bonded to the seal body produced by sealing the mount portion with a sealing glass body, and inserted into the branch pipe portion, and the outer circumferential surface of the seal body covered with quartz glass and the inner wall of the branch pipe portion formed of the glass body. Welded. Moreover, it is a short arc type discharge lamp which has a structure with high stress resistance according to the thickness of the said seal body, the thickness of the said branch pipe part, and the length of the edge part of the said seal body. The concrete structure is shown in the following example.

<Example 1>

As a first embodiment of the present invention, a schematic cross-sectional view of an enlarged view of the seal portion is shown in FIG. The short arc type discharge lamp 1 of this invention consists of the branch pipe part 3 which protrudes from the bulb part 2. In addition, the inner lead rod 6 is disposed through the tubular body 7, and a metal body 8 is disposed at the end 6a side of the lead rod 6 to be welded to the lead rod 6. have. A metal foil 9 is connected to the metal body 8, and the metal foil 9 is disposed on the outer circumference of the occluded body 10. In addition, although the metal foil 9 is typically described in FIG. 1, the actual thickness dimension is about 20 micrometers, for example. The second metal body 11 is arranged on the other end side of the metal foil 9 and is connected to the metal foil 9. In addition, an external lead rod 13 is connected to the second metal body 11. Moreover, the said outer lead rod 13 is arrange | positioned through the 2nd tubular body 12 which consists of quartz glass. Further, the inner lead rod 6, the tubular body 7, the metal body 8, the metal foil 9, the blockage body 10, the second metal body 11, the second tubular body ( 12) The mount part 14 is comprised by the external lead rod 13. As shown in FIG. The sealing glass body 15 is arrange | positioned on the outer periphery of the said mount part 14, and is sealed with the part of the said metal foil 9, and forms the sealing body 16. As shown in FIG. The seal body 16 is inserted into the branch pipe part 3 so that the inner wall of the pipe of the branch pipe part 3 and the outer circumferential surface of the seal body 16 are welded. In addition, although the shape of the sealing glass body 15 is substantially cylindrical in FIG. 1, the shape, such as forming the taper which spreads to the outer diameter side in the inner diameter side edge part of the said sealing glass body 15, may be sufficient.

Moreover, d is the thickness of the glass body which comprises the branch pipe part 3, b is the thickness of the said glass body 15 for sealing, and the said tubular body 7 from the edge part at the side of the said bulb 2 of the said seal body 16 is carried out. Let the distance to the edge part at the side of the said bulb 2 of () be a. In this case, there exists a point c at which stress is most concentrated among the stages of the bulb 2 side of the seal body 16 and the end of the branch pipe part 3 side. . The relationship with each value of said a, b, c in the point c which the said stress concentrates is shown in FIG.

Fig. 2 is obtained by stress analysis simulation and is a result of calculation under a pressure condition of 3 MPa as the internal pressure of the bulb 2. On the vertical axis, stress generated during the lighting of the short arc-type discharge lamp 1 at point c, and on the horizontal axis, the bulb of the tubular body 7 is formed from an end of the bulb 2 side of the seal body 16. The distance a to the end of the side 2) is divided by the thickness b of the sealing glass body 15, and specifically, the length a of the a when the thickness b is shown. In addition, the stress of the point c in each a / b is the distance a = from the edge part at the side of the said bulb 2 of the said seal body 16 to the edge part at the side of the said bulb 2 of the said tubular body 7 == 0, that is, the stress generated at the point c when the end of the bulb 2 side of the seal body 16 and the end of the bulb 2 side of the tubular body 7 are in the same plane is set to 100. Normalized to the stress of the case. According to FIG. 2, the stress which generate | occur | produces in each value of a / b when the value of b is set to 1.5, 2, and 3 is shown. In the entirety of each b, at a / b> 2, the stress is almost stable at the value of each b, and all values are smaller than the case where a / b = 0. That is, the stress of the point c can be reduced as it is a range of a / b> 2. In addition, as a pseudo confirming experiment, a short arc discharge lamp having the same shape as that used in the simulation was produced, and the breakdown voltage test was performed. As a result, the lamp corresponding to a / b> 2 does not break up to a higher pressure than the lamp corresponding to a / b = 0, and the stress concentration at point c becomes less than a / b> 2. I think.

Next, as shown in FIG. 3 and the calculation result by the stress analysis simulation, it calculates on the pressure conditions of 3 MPa as the internal pressure of the bulb 2. In FIG. 3, when the thickness b of the sealing glass body 15 and the thickness d of the glass body constituting the branch pipe part 3 are equal to each other, the stress generated at the point c is normalized to 100. The horizontal axis represents the value of b / d. According to FIG. 3, when b / d = 1, ie, when the thickness b of the said sealing glass body 15 becomes thick rather than the case where the thickness of b and d is the same, the stress which arises also tends to become high. On the contrary, the stress which arises when b / d <1 shows a tendency to become lower than the case where b / d = 1. In addition, as a pseudo confirming experiment as in the case of FIG. 2, a short arc discharge lamp having the same shape as that used in the simulation was produced, and the breakdown voltage test was performed. As a result, the lamp corresponding to b / d <1 is not destroyed to a higher pressure than the lamp corresponding to b / d = 1, and the stress concentration at the point c becomes less than that under the condition of b / d <1. I think.

2 and 3, in the case of a / b> 2 and b / d <1, there is an advantage in that the stress generated at the point c at which the stress concentrates can be particularly reduced. Specifically, the glass body 15 for sealing the distance a from the edge part at the side of the bulb 2 of the seal body 16 to the end portion at the side of the bulb 2 of the tubular body 7 is 15 mm. ), Thickness b of 2 mm and the thickness d of the glass body which comprises the said branch pipe part 3 were 3.5 mm. In this case, the value of a / b is 4, and the value of b / d is 0.57. The branch pipe part 3 has a diameter of 32 mm and a length of 65 mm.

In the embodiment having the above-described configuration, for example, the input power 12kW, the size of the anode is 60mm in length, 30mm in outer diameter, about 1Kg in weight, 120mm in diameter of the bulb portion, 160mm in the bulb portion, encapsulated in the bulb portion A short arc discharge lamp having 8 mg / kW of mercury encapsulated in the bulb portion and Xe as a rare gas was produced and lit, but no problems such as bending of the branch pipe portion occurred. Moreover, in the short arc discharge lamp whose input electric power is 10 kW or more, generation | occurrence | production of stress is suppressed by the said structure, and the problem, such as a branch pipe bending, can be eliminated. This is the same even when the pressure in the bulb portion at the time of lighting is increased by the rare gas or the amount of mercury. For example, in the short arc discharge lamp used for semiconductor exposure or the process of a liquid crystal substrate, the pressure of the rare gas enclosed in the said bulb part is 0.1 to 5 atmospheres, and the amount of mercury enclosed in the said bulb part is 1 mg / There exists a thing of 9-10 mg / dl, and the same effect can be expected in these.

Next, an example of the sealing process for manufacturing the short arc discharge lamp which has the structure of this invention is shown in FIG. The sealing part of this invention is comprised by each process from a) to g) of FIG. a) is a figure which shows the structure of a mount part. The inner lead rod 6 is fitted with a tubular body 7 made of quartz glass. Moreover, the metal foil 9 is connected to the washer-shaped metal body 8 welded to the said inner lead rod 6. One end of the inner lead rod 6 is inserted into one end of a block 10 made of quartz glass. An outer lead rod 13 is inserted into the other end of the obturator 10. The second metal body 11 is welded to the external lead rod 13, and the other end of the metal foil 9 is connected to the second metal body. The metal foils 9 are arranged on the outer circumferential surface of the occluded body 10 at equal intervals. In addition, a second tubular body 12 is inserted into the outer lead rod 13. In b), the mount portion 14 combined in a) is inserted into the sealing glass body 15. In c), the said metal foil 9 of the said mount part 14 is foil-sealed by heating the said glass body 15 for sealing. As a result, the inner lead rod 6 and the outer lead rod 13 can be energized in a state of keeping airtight. In d), the both ends of the said sealing glass body 15 are cut | disconnected. In this step, the dimension of a, which is the distance between the occluded body 10 and the end of the sealing glass body, is defined. Thereby, the sealing body 16 is comprised. In the process of e), the positive electrode 44 or the negative electrode 45 is connected to the tip of the inner lead rod 6 protruding from the seal body 16 as an electrode. In f), the sealing body 16 with an electrode manufactured by e) is inserted into the branch pipe part 3 which protrudes from the bulb part 2. In g), the outer peripheral surface of the said seal body 16 inserted by heating the said branch pipe part 3, and the inner wall of the pipe part of the said branch pipe part are welded. The seal | sticker of this invention is comprised by the said process.

According to the short arc type discharge lamp of the present invention, a sealing body having the metal foil portion sealed with a sealing glass body having an inner diameter larger than the outer diameter of the mount portion is disposed in the branch pipe portion, and the branch pipe portion and the seal body are welded. Have According to the said structure, the problem which wrinkles generate | occur | produce in the said metal foil at the time of manufacture, or a large stress is applied to the said metal foil can be eliminated. Moreover, the airtightness of the said metal foil part can be ensured by sealing the said metal foil in advance to the sealing glass body. In addition, the sealing member is sealed to the branch pipe portion, whereby the electrode portion becomes large and the sealing portion can be easily formed even if the weight becomes very heavy.

In addition to the above-described configuration, an end portion of the tubular body supporting the inner lead rod disposed on the inner lead rod side of the seal body and an end portion of the discharge space side of the sealing glass body formed on an outer surface of the seal body. A / b> 2, and b / d <when a distance to a is made b and the glass thickness of the radial direction of the glass tube which comprises the said branch pipe part is set to b, the glass thickness of the radial direction of the said sealing glass body. By satisfying the relationship of 1, it becomes possible to suppress the stress which arises in the said seal part small. Accordingly, even if the short arc discharge lamp becomes large in size with an input power of 10 kW or more, breakage such as bending at the branch pipe part due to the weight of the electrode is suppressed. Moreover, even if the pressure in a bulb part is high at the time of lighting, there exists an effect that a problem, such as a branch pipe part bending, does not arise.

1 is a schematic cross-sectional view showing the structure of a seal portion of a short arc type discharge lamp of the present invention;

2 is a diagram showing the effect of the present invention;

3 is a diagram showing the effect of the present invention;

4 is a conceptual diagram showing a manufacturing process of the short arc type discharge lamp of the present invention;

5 is a conceptual diagram showing the structure of a conventional short arc type discharge lamp.

<Description of the symbols for the main parts of the drawings>

1: short arc type discharge lamp 2: bulb part

3: branch pipe part 6: inner lead rod

6a: end 7: tubular body

8: metal body 9: metal foil

10: occlusion body 11: second metal body

12: second tubular body 13: outer lead rod

14 mount portion 15 sealing glass body

16: seal 44: anode

45 cathode 51: short arc discharge lamp

52: bulb part 53: branch pipe part

54: anode 55: cathode

56a: internal lead rod 56b: internal lead rod

57: tubular body 58: metal body

59: metal foil 60: obturator

60a: gap 61: metal body

62: tubular body 63: external lead rod

64: mount unit

Claims (2)

A bulb portion forming a discharge space, a branch pipe portion protruding from both ends of the bulb portion, and a pair of electrodes are disposed to face each other in the bulb portion, and the branch pipe portion includes an internal lead rod connected to the electrode; A tubular body for supporting the inner lead rod, a metal body electrically connected to the inner lead rod, a metal foil portion in contact with the metal body, a blockage body on which the metal foil portion is disposed on an outer circumferential surface, and disposed on an end side of the closure body A short arc discharge lamp having a second metal body electrically connected to the metal foil portion, and a mount portion having an external lead rod connected to the second metal body to enable power supply from the outside. The sealing body which sealed the said metal foil part with the sealing glass body which has an inner diameter larger than the outer diameter of the said mount part is arrange | positioned in the said branch pipe part, The said branch pipe part and said seal body are welded, The short arc type discharge lamp characterized by the above-mentioned. The distance from the end of the tubular body supporting the inner lead bar disposed on the inner lead bar side of the seal body to the end of the discharge space side of the sealing glass body provided on the outer surface of the seal body. When a, the glass thickness of the radial direction of the said glass body for sealing is b, and the glass thickness of the radial direction of the glass tube which comprises the said branch pipe part is d, a / b> 2 and b / d <1 Short arc-type discharge lamp, characterized in that to satisfy the relationship.